An inspection device of that type is illustrated, for example in Document FR-A-2 443 047.
That inspection device thus includes two parallel measurement arms of semi-cylindrical section that project from a common base: the arms can move apart from each other by bending so as to inspect bores by means of the associated contactors. Such a device is therefore unsuitable for inspecting outside diameters. In addition, the deformable system uses a V-shaped spring blade that co-operates via a metal wire with a differential transducer: the device is thus necessarily bulky, and its accuracy remains limited by the great length of wire used for transmitting motion.
An analogous device is described in document U.S. application Ser. No. 4,881,324: the corresponding deformable one-piece unit includes two resilient bridges for directly connecting the support of the axially movable transducer to the two measurement arms, and four resilient bridges forming a hinged parallelogram.
Other inspection devices have also been proposed that make use of a U-shaped deformable unit. Thus, document EP-A-0 181 460 describes a device having two independent U-shaped units, each unit having three measurement arms hinged on a common base: a separation sensor is then associated with each pair of arms, and this is done for each unit, with measurement being performed by comparing corresponding signals. Other variants, likewise based on the principle of a deformable U-shape, with a differential transducer mounted between the branches thereof, are also described in document EP-A-0 292 767.
Finally, the state of the art is illustrated by documents U.S. application Ser. No. 3,958,337 and U.S. application Ser. No. 3,958,338 which describe analog gauges specially designed for inspecting small-diameter bores. Such gauges nevertheless constitute a structure that is complex and expensive to manufacture.
An object of the invention is to provide an inspection device that avoids the above-mentioned drawbacks and/or limitations.
Another object of the invention is to design a device whose structure makes it possible both to inspect bores and to inspect outside diameters, while nevertheless providing high accuracy in both cases.
A further object of the invention is to provide an inspection device which is both compact and easy to install.